Add Timeout field to CheckMonitor

command/agent/agent.go

@@ -968,6 +968,7 @@ func (a *Agent) AddCheck(check *structs.HealthCheck, chkType *CheckType, persist
 				CheckID:  check.CheckID,
 				Script:   chkType.Script,
 				Interval: chkType.Interval,
+				Timeout:  chkType.Timeout,
 				Logger:   a.logger,
 				ReapLock: &a.reapLock,
 			}

command/agent/check.go

@@ -101,6 +101,7 @@ type CheckMonitor struct {
 	CheckID  string
 	Script   string
 	Interval time.Duration
+	Timeout  time.Duration
 	Logger   *log.Logger
 	ReapLock *sync.RWMutex
 
@@ -180,7 +181,11 @@ func (c *CheckMonitor) check() {
 		errCh <- cmd.Wait()
 	}()
 	go func() {
-		time.Sleep(30 * time.Second)
+		if c.Timeout > 0 {
+			time.Sleep(c.Timeout)
+		} else {
+			time.Sleep(30 * time.Second)
+		}
 		errCh <- fmt.Errorf("Timed out running check '%s'", c.Script)
 	}()
 	err = <-errCh

command/agent/check_test.go

@@ -82,6 +82,36 @@ func TestCheckMonitor_BadCmd(t *testing.T) {
 	expectStatus(t, "foobarbaz", structs.HealthCritical)
 }
 
+func TestCheckMonitor_Timeout(t *testing.T) {
+	mock := &MockNotify{
+		state:   make(map[string]string),
+		updates: make(map[string]int),
+		output:  make(map[string]string),
+	}
+	check := &CheckMonitor{
+		Notify:   mock,
+		CheckID:  "foo",
+		Script:   "sleep 1 && exit 0",
+		Interval: 10 * time.Millisecond,
+		Timeout:  5 * time.Millisecond,
+		Logger:   log.New(os.Stderr, "", log.LstdFlags),
+		ReapLock: &sync.RWMutex{},
+	}
+	check.Start()
+	defer check.Stop()
+
+	time.Sleep(50 * time.Millisecond)
+
+	// Should have at least 2 updates
+	if mock.updates["foo"] < 2 {
+		t.Fatalf("should have at least 2 updates %v", mock.updates)
+	}
+
+	if mock.state["foo"] != "critical" {
+		t.Fatalf("should be critical %v", mock.state)
+	}
+}
+
 func TestCheckMonitor_RandomStagger(t *testing.T) {
 	mock := &MockNotify{
 		state:   make(map[string]string),

website/source/docs/agent/checks.html.markdown

@@ -22,6 +22,9 @@ There are five different kinds of checks:
   generates some output. A script is paired with an invocation interval (e.g.
   every 30 seconds). This is similar to the Nagios plugin system. The output of
   a script check is limited to 4K. Output larger than this will be truncated.
+  By default, Script checks will be configured with a timeout equal to 30 seconds.
+  It is possible to configure a custom Script check timeout value by specifying the 
+  `timeout` field in the check definition.
 
 * HTTP + Interval - These checks make an HTTP `GET` request every Interval (e.g.
   every 30 seconds) to the specified URL. The status of the service depends on the HTTP response code:
@@ -83,7 +86,8 @@ A script check:
     "id": "mem-util",
     "name": "Memory utilization",
     "script": "/usr/local/bin/check_mem.py",
-    "interval": "10s"
+    "interval": "10s",
+    "timeout": "1s"
   }
 }
 ```